package Thread.Thread_Security;

class Counter{
    public int count=0;
    public void add(){
        synchronized (this){
            //谁调用this就指代谁
            count++;
        }
    }
}
public class Demo21 {
    public static void main(String[] args) throws InterruptedException {

        Counter counter=new Counter();
        Thread t1=new Thread(()->{
            for (int i = 0; i < 50000; i++) {
                counter.add();
//                synchronized (counter) {
//                    counter.add();
//                }
            }
        });
        Thread t2=new Thread(()->{
            for (int i = 0; i < 50000; i++) {
                counter.add();
//                synchronized (counter) {
//                    counter.add();
//                }
            }
        });
        t1.start();
        t2.start();
        t1.join();
        t2.join();
        System.out.println(counter.count);
    }
}
